OBJECTIVE: To find the changes, as a function of aging, in the abilities concerned with preparation. It is hoped that the proposed series of experiments, because of stronger methodology, will avoid the many traps fallen into by the considerable number of earlier investigations which have almost unanimously agreed that older people lack the ability to prepare. Outstanding performers on reaction-time tasks will be selected in four age ranges covering the span of 17 to 80 years. They will then be experimented upon over a period of three years. The attaining and maintaining of preparation will be assessed for both simple and choice reactions. Techniques will be used which separate these abilities and which eliminate the contaminants of time estimation and memory. Ability to utilize an information-reducing cue will be assessed both for separated responses and for serial performance. In each of the studies, thorough prior training will be employed. Moreover, self-adaptive methods will be used to reduce any effects of difference in motivation of cautiousness.